1. Field of the Invention
This invention relates to a rubber plug fitting apparatus for fitting a rubber plug over a wire end.
2. Description of the Related Art
A known conventional rubber plug fitting apparatus is disclosed in a Japanese Patent Application, Laid-Open Publication No. Hei-9-260008. This rubber plug fitting apparatus has a rubber plug supply section, a rubber plug receiving section and a rubber plug fitting section. The rubber plug supply section serves to align rubber plugs to sequentially feed them to the rubber plug receiving section. The rubber plug receiving section serves to transport the rubber plugs supplied from the rubber plug supply section to the rubber plug fitting section. The rubber plug fitting section holds a rubber plug with an opposed rubber plug holder pair and brings the rubber plug close to a wire end held separately to fit the rubber plug over the wire end.
As shown in FIG. 1, the rubber plug fitting section has a pair of rubber plug holders 1, 1 each screwed to supporting blocks 2, 2. The rubber plug holders 1, 1 each have recesses 4, 4 in the opposed surfaces for accommodating a rubber plug. The rubber plug fitting section also has a pair of insertion guides 6, 6 screwed to a pair of insertion guide supporting blocks 5, 5 as shown in FIG. 1. The insertion guides 6, 6 have insertion pipe halves 7, 7 in a protruding manner, a pipe being divided along the central axis thereof. The insertion pipe halves 7, 7 are joined to constitute a pipe to be inserted into a tubular hole of a rubber plug 3.
The insertion guide supporting blocks 5, 5 are provided to be movable with respect to the holder supporting blocks 2, 2 so as to insert the insertion pipe halves 7, 7 into the tubular hole of the rubber plug 3 held between the rubber plug holders 1, 1. The pipe formed with the joined insertion pipe halves 7, 7 serves to secure a wire insertion space in the rubber plug 3. In this rubber plug fitting apparatus, the rubber plug holders 1, 1 and the insertion guides 6, 6 are changed in accordance with a kind or size of the rubber plug to be fitted, thereby to handle various kinds of rubber plugs.
However, in the above conventional rubber plug fitting apparatus, the rubber plug holders 1, 1 are screwed to the holder supporting blocks 2, 2 and the insertion guides 6, 6 are screwed to the insertion guide supporting blocks 5, 5, which arrangement requires much time to change the parts and skills of adjusting the degree of screwing or the like. Thus every time the size or kind of the rubber plug 3 is changed, the operation of the apparatus is entirely suspended for a long time, which prevents reduction in cost of fitting rubber plugs.
This invention has been achieved with such points in mind.
It is therefore an object of the invention to provide a rubber plug fitting apparatus which takes short time to change parts and provide easy and positive change of the parts.
According to a first aspect of the invention, there is provided a rubber plug fitting apparatus which comprises a rubber plug holder for holding a rubber plug to be fitted over a wire end, and a holder supporting block to which the rubber plug holder is detachably attached, the rubber plug holder comprising a fixed arm configured to be inserted and fixed into the holder supporting block, and an operatively pushed part formed at an end of the fixed arm, and the holder supporting block comprising a slot into which the fixed arm is inserted and fitted and from which the operatively pushed part is protruded on the side opposite to the insertion side, and
a fixing means for fixing the fixed arm inserted and fitted into the slot with the insertion of the fixed arm into the slot, and allowing the fixed arm to be pulled out of the slot at a press of the operatively pushed part.
Thus in this invention, the operatively pushed part and the fixed arm of the rubber plug holder are inserted into the holder supporting block to fix the fixed arm into the holder supporting block. At that time, the operatively pushed part is protruded from the slot of the holder supporting block on the side opposite to the insertion side. The fixing means fixing the fixed arm to the holder supporting block is set to allow the fixed arm to be pulled out of the slot by a push of the operatively pushed part protruded from the side opposite to the insertion side of the slot.
Thus in this structure, in order to detach the rubber plug holder from the holder supporting block, the operatively pushed part is pushed instead of pulling out the rubber plug holder, which improves the workability. More specifically, if the part of the rubber plug holder positioned on the insertion side of the holder supporting block is gripped to be pulled out, the rubber plug holder should be held on both sides, which provides low workability. In this structure, only a push of the operatively pushed part can easily detach the rubber plug holder from the holder supporting block.
According to a second aspect of the invention, the fixing means comprises a ball provided in an internal wall of the slot and arranged to be engaged with the fixed arm inserted and fitted into the slot, and a biasing means for biasing the ball to the slot side to engage the ball with the fixed arm inserted and fitted into the slot.
Thus in this invention, the ball provided in the internal wall of the slot of the holder supporting block presses the fixed arm with the biasing means, thereby to fix the rubber plug holder to the holder supporting block positively, providing a tactile feel. Thus the attachment/detachment of the rubber plug holder to/from the holder supporting block is easily performed.
More specifically, when the fixed arm of the rubber plug holder is inserted in the slot, the fixed arm of the rubber plug holder is pushed against the pressing force of the ball by confirming a click touch or a click feeling, thereby being pressed and fixed by the ball. On the other hand, when the fixed arm being removed, the operatively pushed part is pushed against the biasing force of the ball to push the ball up, thereby to detach the rubber plug holder easily.
According to a third aspect of the invention, the fixed arm is provided with a recess with which the ball is engaged.
According to a fourth aspect of the invention, the recess is a V-shaped groove.
Thus in this invention, the engagement of the ball with the recess formed in the fixed arm inserted into the slot fixes the rubber plug holder, and the disengagement of the ball with the recess by a push of the operatively pushed part removes the rubber plug holder. The so-called plunger mechanism provides speedy and positive attachment/detachment of the rubber plug holder, eliminating a cumbersome task such as screwing, and requiring no special skills.